#include <forward_list>
#include <iostream>
#include <string>
#include <vector>
using namespace std;

void print(int a, int b, int c) { cout << a << " " << b << " " << c << endl; }

struct V {
  int a;
  int val() const {
    cout << "call\n";
    return a;
  }
};

#define LOOP_1DF(i, imin, imax) for (int i = imin; i <= imax; ++i)

int main() {

  V b{5};
  /// 仅仅是文字替换
  const int val = b.val();

  LOOP_1DF(i, 0, val) { cout << "\nn"; }
  return 0;
}